Neutrino Astronomy

1. Dan Hooper, Tim Linden, Abby Vieregg
2. 1810.02823

Recent IceCube observations of the flaring blazar TXS 0506+056 have excited the community, potentially providing the first detection of a neutrino source. Additionally, the detection of neutrino emission from a blazar might indicate that blazars dominate the neutrino background. Here, however, we utilize detailed catalogs of optically and gamma-ray bright blazars, including a huge population of source that could potentially produce the diffuse IceCube neutrino emission. We find no evidence of neutrino hotspots associated with the known positions of blazars, and use this lack of correlation to rule out models where more than approximately 20% of the diffuse IceCube neutrino background is produced by blazar activity.